Electrical switchgear devices may be used for breaking a fault current in a circuit in the event of a fault, in order to limit damages which may be caused due to the fault current. An electrical switchgear device may comprise a plurality of movable contact fingers which are thrown away at a fast speed from a fixed contact or electrode upon a tripping operation. The movable contact fingers are parallel connected when in mechanical connection with the fixed contact, thereby dividing the current in a number of components equal to the number of movable contact fingers. Larger currents may thereby be handled by the electrical switchgear device.
In the event of a fast electric fault which creates a fault current of a large amplitude, it would generally be desirable to be able to trip the circuit as fast as possible. U.S. Pat. No. 6,777,635 discloses a very high-speed limiting electrical switchgear apparatus which comprises a circuit for handling fast electric faults with currents of large amplitude. The switchgear apparatus comprises a coil which is connectable to a voltage source in the event of a fault, wherein a Thomson effect thruster is thrown away from the coil towards the contact fingers. As a result, the contact fingers pivot clockwise, thus breaking the contact with fixed contacts, wherein a latch catches the contact fingers before they fall back into contact position.
Although the disclosure of U.S. Pat. No. 6,777,635 provides fast tripping, it would still be desirable to provide an even faster and more robust electrical switchgear device.